Ion trap
An ion trap is a combination of electric or magnetic fields that captures ions in a region of a vacuum system or tube. Ion traps have a number of scientific uses such as mass spectrometery and trapping ions while the ion's quantum state is manipulated. The two most common types of ion traps are the Penning trap and the Paul trap (quadrupole ion trap).
When using ion traps for scientific studies of quantum state manipulation, the Paul trap is most often used. This work may lead to a trapped ion quantum computer[1] and has already been used to create the world's most accurate atomic clocks.[2]
An ion trap mass spectrometer may incorporate a Penning trap (Fourier transform ion cyclotron resonance),[3] Paul trap[4] or the Kingdon trap.[5] The Orbitrap, introduced in 2005, is based on the Kingdon trap.[6] Other types of mass spectrometers may also use a linear quadrupole ion trap as a selective mass filter.
In an electron gun (a device emitting high-speed electrons, such as those in CRTs), an ion trap may be implemented above the cathode (using an extra, positively-charged electrode between the cathode and the extraction electrode) to prevent its degradation by positive ions accelerated backward by the fields intended to pull electrons away from the cathode.
Penning ion trap
Penning trap is used for the storage of charged particles using a constant static magnetic field and a spatially inhomogeneous static electric field.
Paul ion trap
A Paul trap uses static direct current (DC) and radio frequency (RF) oscillating electric fields to trap ions.
Kingdon trap
A Kingdon trap consists of a thin central wire and an outer cylindrical electrode. A static applied voltage results in a radial logarithmic potential between the electrodes.[7]
Cathode ray tubes
Devices known as ion traps were used in early television receivers, prior to the introduction of aluminized CRT faces in approximately 1958. The ion trap must be delicately adjusted for maximum brightness.[8][9] The purpose of these devices was to prevent ions from discoloring the phosphor screen.[10]
See also
References
- ^ R. Blatt and D. J. Wineland (2008). "Entangled states of trapped atomic ions" (PDF). Nature. 453 (7198): 1008–1014. Bibcode:2008Natur.453.1008B. doi:10.1038/nature07125. PMID 18563151.
- ^ T. Rosenband, D. B. Hume, P. O. Schmidt, C. W. Chou, A. Brusch, L. Lorini, W. H. Oskay, R. E. Drullinger, T. M. Fortier, J. E. Stalnaker, S. A. Diddams, W. C. Swann, N. R. Newbury, W. M. Itano, D. J. Wineland, and J. C. Bergquist (2008). "Frequency Ratio of Al+ and Hg+ Single-Ion Optical Clocks; Metrology at the 17th Decimal Place" (PDF). Science. 319 (5871): 1808–1812. Bibcode:2008Sci...319.1808R. doi:10.1126/science.1154622. PMID 18323415.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Blaum, Klaus (2006). "High-accuracy mass spectrometry with stored ions". Physics Reports. 425 (1): 1–78. Bibcode:2006PhR...425....1B. doi:10.1016/j.physrep.2005.10.011.
- ^ Douglas, D.J. (2005). "Linear ion traps in mass spectrometry". Mass Spectrometry Reviews. 24 (1): 1–29. doi:10.1002/mas.20004. PMID 15389865.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ Kingdon KH (1923). "A Method for the Neutralization of Electron Space Charge by Positive Ionization at Very Low Gas Pressures". Physical Review. 21 (4): 408–418. Bibcode:1923PhRv...21..408K. doi:10.1103/PhysRev.21.408.
- ^ Hu, QZ (2005). "The Orbitrap: a new mass spectrometer". Journal of Mass Spectrometry. 40 (4): 430–443. doi:10.1002/jms.856. PMID 15838939.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ Kingdon KH (1923). "A Method for the Neutralization of Electron Space Charge by Positive Ionization at Very Low Gas Pressures" (subscription required). Physical Review. 21 (4): 408. Bibcode:1923PhRv...21..408K. doi:10.1103/PhysRev.21.408.
- ^ Magnet for cathode-ray tube ion traps
- ^ Ion Trap for a Cathode Ray Tube
- ^ Hartson, Ted (2004). "How the World Changed Television" (PDF). Retrieved 2008-10-13.
External links
- VIAS Science Cartoons A cranky view of an ion trap...
- Paul trap
| Ion source | |
|---|---|
| Mass analyzer | |
| Detector | |
| MS combination | |
| Fragmentation | |
